A floor jack is a rigid jacking device used as a small and light lifting tool for lifting heavy objects within a small stroke of a support base at the top of the floor jack. The floor jack is an important hydraulic tool widely used for cars or movable equipments to support the weight of a car or moving equipment in order to adjust the equipment and mainly used for car repairs or other lifting and supporting jobs in factories, mines, or traffic departments. The floor jack generally comprises a chassis, a cylinder, a lever and a lifting frame, and a chassis is the main support part of the floor jack, so that the strength of the chassis is the most important parameter to the floor jack.
At present, an automobile floor-jack chassis side panel available generally adopts a single-layer steel sheet, a bent single-layer steel sheet, or a reinforcing board attached onto the aforementioned steel sheets, and such design has the following problems:    1. The structure of the single-layer steel sheet or the bent single-layer steel is made of a uniform thickness, and thus cannot reinforce the portion having the largest load or force exerted thereon. To meet the load carrying requirement, the thickness of the steel sheet must be increased, and thus causing an unnecessary waste of material and a low utilization of the material,    2. Even though the reinforcing board is attached onto the surface of the aforementioned steel sheets to partially reinforce the structure to a certain extent, yet such design cannot overcome the problem of the low anti-bending ability and the poor overall aesthetic look of the product.
Therefore, it is an important and urgent subject for related manufacturers to develop a chassis side panel with the high utilization rate and anti-bending ability.